$(-\infty, -2)$ Refer to the image below for the graph.
Work Step by Step
Subtract $11$ on both sides to obtain: $3x \lt -6$ Divide by $3$ on both sides to obtain: $x \lt -2$ The solution set is the set of real numbers less than $-2$. In interval notation, the solution set is: $(-\infty, -2)$ To graph this inequality, plot a hole (or hollow dot) at $x=-2$ then shade the region to its left. (refer to the attached image in the answer part)